Something sure seems amiss here. Anything is possible, but I seems HIGHLY unlikely that snake could grow to be 35+ inches in three months and nearly IMPOSSIBLE for such to be accomplished eating only pinkies. Is it possible you are mistaken concerning the dimensions of the tank you're using?
If you will take a picture of your snake directly from above, with somthing of known length (a ruler works well), I'd be happy to measure him accurately with Serp's measuring program. That would confirm what you're saying for us all.